Communication protocol, Ascii, polled, Communication protocol ascii, polled – Vaisala WMT52 User Manual

Page 125

Advertising
background image

Appendix A ______________________________________________________________ Networking

VAISALA______________________________________________________________________ 123

Communication Protocol

Set the communication protocol to ASCII polled (with or without CRC)
or NMEA query. When using NMEA query, the wind message should
be set to XDR (aWU,N=T).

ASCII, Polled

WMT52s on the bus shall be assigned with different addresses. (for
example: aXU,A=0,1,2, ... ).

Example (a bus with three WMT52s):

WMT52 #1 communication settings:
0XU,A=0,M=P,C=3,I=0,B=19200,D=8,P=N,S=1,L=25

WMT52 #2 communication settings:
1XU,A=1,M=P,C=3,I=0,B=19200,D=8,P=N,S=1,L=25

WMT52 #3 communication settings:
2XU,A=2,M=P,C=3,I=0,B=19200,D=8,P=N,S=1,L=25

Example (composite data message queries to the sensors 1 and 3 are
assigned as follows):

0R0<cr><lf>

1R0<cr><lf>

2R0<cr><lf>

NOTE

No matter which communication protocol, ASCII polled or NMEA
query is chosen, the error messaging parameter of the supervisor
message must be disactivated with aSU,S=N for each WMT52 on the
bus in order to prevent the units responding to the commands not
assigned to them.

Advertising